Vintage bottom bracket trouble

[anfosverige]

I am in the midst of renovating a late 40s ( I think) Gameson road path frame. I’ll post pics when I find out how and once I’m qualified to do so.

Took the frame to lbs to have bottom bracket fitted ( the one job that I hate doing myself). Got a call to say that the threads were destroyed and that they couldn’t fit a new bottom bracket. In a state of new despair, I rushed over to see what was wrong.

They showed how the bb cartridge didn’t make contact with the bb shell. They advised me to throw the frame away!

After retrieving the frame from them, I took a closer look and saw that the threads are fine and that the bb shell is, in fact, considerably larger than a standard bb shell. A bit of googling later, I now strongly suspect that the frame was built to take a 1.45 inch diameter Chater Lea bottom bracket (usually intended for tandems but sometimes used on solo machines). I’ve measured the bb diameter to 36mm; allowing for the depth of the threads, this should equate to 1.45 inches (36.8mm). I’ve only found reference to the Chater Lea oversized bottom bracket. Are there any other odd bb sizes that could account for the diameter of the bb shell?

Further research leads me to the following conclusions:

- I find a 1.45 inch Chater Lea bottom bracket
- I use sleeves available from the tandem club
- I buy a Phil Wood bb and appropriate mounting rings
- I buy Phil Wood mounting rings and find a cheaper bb to use with it.

I can’t really justify the expense of the full Phil Wood option and oversized Chater Lea bottom brackets are, I understand, very rare (and likely to be expensive).
The sleeves from the tandem club look promising. I would also consider the Phil Wood mounting rings combined with a cheaper bb except it seems tricky to find a compatible bb.

Has anyone experienced this issue? Any advice on how to solve this would be very gratefully received.

 

[keithglos]

Chater lea would have been a cast shell, possibly find the name on the casting, although Bill would have filed it. Chater large bracket cups used 5/16 balls, so unlikely to fit a cotterles axle. some tandem mods are a possibility.

 

[anfosverige]

Thanks for the info.

It seems to be a cast shell but, as you suggest, it looks like the manufacturer's name must have been filed away.

The tandem club sleeves look like the best value option given the cost of the Phil Wood (they do mounting rings for 1.45 inch bb shells).

The only vintage bb, with this sort of diameter, I could find reference to is the Chater Lea 1.45 in. I just wanted to be sure that there weren't any other odd-sized bb diameters before I invested.

 

[bm0p700f]

Would it be possible to get a new Italian thread cut 36mmx24tpi and fit a modern Italian cotterless BB. It might be your only way out.

If it works ust remember to check the cups regularly.

 

[keithglos]

Going back in time some Chater bottom brackets were 1 7/16 inches,
about 36.5mm, but may have been 26 tpi. I don't think the 36 mm would work, too much slack, and changing the right side to right hand thread.

 

[bm0p700f]

There must be press fit BB for Italian BB shells that have knackered threads and have had there threads removed.

Someone must make some. They exist for English BB sizes.